The generation of three dimensional (3D) content, particularly 3D animated content, is becoming more popular. Animated 3D content is typically included in animated movies, virtual storytelling, 3D animations for video games in particular the cut away scenes in the game, 3D simulations of industrial uses, teleconferencing, and social interaction. Despite these emerging uses, the creation of 3D characters that can be animated is still typically only performed by artists that have specialized training in animation. Specifically, the creation of an animated sequence with one or more characters often requires a group of specialized 3D animation artists and animators.
The most difficult process in generating an animated sequence is the creation of a rigged mesh for an animated character. For purposes of this discussion, a mesh is a set of polygons (segments) defining the surface of an object or character; and a rigged mesh is a mesh that further includes a skeleton or set of bones and skinning weights. The skeleton or bone set is used to define character movement; and skinning weights are a set of relations that govern the motion of the mesh polygons (segments) with respect to the underlying skeleton. The creation of the skeleton or bone set often requires identifying key points of the character mesh. These key points may include, but are not limited to corners of a mouth, corners of the eyes, and other features important for movement. Typically, the process or creating the skeleton and skinning weights is performed by an animation process performed manually herein after termed forward kinematic rigging.
Animation of a rigged 3D character can be achieved by motion applied to the bones which drive the mesh. Animation may also be obtained using blend shapes on a per vertex animation using a manually intensive process. The bone set and skinning weights may be converted into a blend shape animation process by identification of appropriate morph targets.